基于贪婪策略的NAND FLASH存储器的磨损均衡算法研究

Research on Wear Leveling Algorithm of NAND FLASH Memory Based on Greedy Strategy

NAND FLASH存储器是无线传感器网络节点的存储设备。传感器节点在监控区域中不断获取数据信息,并进行节点之间的数据交互,使得NAND FLASH存储器频繁地进行写操作,从而造成物理块的擦除次数不均衡,缩短了存储器的使用寿命,最终影响整个传感器网络的使用寿命。针对上述问题,提出了贪婪策略的分区地址映射磨损均衡算法。该算法根据磨损擦除的参数进行贪婪选择,选择出擦除次数小的物理块进行写操作,而对擦除次数大的物理块进行配置与实验数据迁移,进入等待擦除。通过软件测试的方式,证明了所提算法可以有效地实现并优化NAND FLASH存储器的磨损均衡。

NAND FLASH memory is the storage device of sensor node in wireless sensor network. Sensor nodes conti-nuously acquire data from monitoring area, and exchange data between nodes. Frequently wri ting operations on NAND FLASH memory makes the physical block’s erase number unbalanced and reduces the memory’s life. Accordingly,it will affect the l ife of the whole sensor network. In this paper, a partition address mapping wear leveling algorithm was proposed to solve this problem. In this algorithm, when data is wri tten into memory, a new physical block for wri ting operations is selected according to the wear leveling measurement which it computed wi th greedy methods. And the con-figurat ion and experimental data are exchanged between the old physical block and the new physical block, then the old physical block enters a wait state. It is proved by software testing that the algorithm proposed in this paper can effec-t ively optimize the wear leveling of NAND FLASH memory.